The company, which charges from £95 to more than £10,000 for its services, said that its essays are only meant to provide an "example" of how an "experienced and accomplished academic would approach the question or project you have been set".

In its advertising the company says "we guarantee that you will receive at least the grade you order (1st class, 2:1, 2:2). If not, we'll give you your money back."

However, its terms and conditions stated that this "in no way represents any guarantee ... that were the same written material to be submitted to the client's university or school then the client would receive that degree mark."

Parent Oxbridge Research Group said the guarantee related to the standard of work they provided, not the grade a customer might actually get. The company added that its terms and conditions prohibited submitting one of its essays as a student's own work.

The ASA said that said that the company nevertheless implied that there was a moneyback guarantee if a student submitted a sample essay and did not get the grade they had paid for.

"We considered that the terms and conditions contradicted, rather than clarified, the claim," the ASA said. "We told ORG not to state or imply that they could guarantee grades, or that customers could get their money back, unless they held robust evidence that this was the case."

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